JPH041228A - Production of polycarbonate - Google Patents

Abstract

PURPOSE:To obtain a polycarbonate excellent in heat resistance, hydrolysis resistance and hue by mixing a polycarbonate obtained under specified conditions with a phosphite compound and a hindered phenol compound. CONSTITUTION:A polycarbonate obtained by transesterifying a dihydroxy compound [e.g. 2,2-bis(4-hydroxyphenyl)propane] with a bisaryl carbonate (e.g. diphenyl carbonate) in the presence of a transesterification catalyst (e.g. potassium borohydride) and melt-polycondensing the product is mixed with a phosphite compound, desirably a compound of formula I (wherein R1 is a 1-30C hydrocarbon group) and a hindered phenol compound desirably having a structure of formula II (wherein R2 is R1).

Description

Detailed Description of the Invention (Industrial Application Field) The present invention involves melt polycondensation of a divalent hydroxy compound and a bisaryl carbonate, etc., by a transesterification method in the presence of a transesterification catalyst. Thermal stability obtained by inactivating the catalyst residue by adding a compound and a specific hindered phenol compound
This invention relates to a method for producing high molecular weight polycarbonate with excellent hue and hydrolytic stability.

(Prior Art and Problems to be Solved by the Invention) The heat-stable, two-hue, high-molecular-weight polycarbonate with excellent hydrolytic stability can be used in a wide range of applications, particularly for injection molding or as a glass sheet in place of window glass. It has a purpose. It is a general-purpose engineering thermoplastic. Although the interfacial polycondensation method is generally effective for producing polycarbonate, it has drawbacks such as the use of toxic phosgene and the fact that chlorine ions remain in the polycarbonate produced. In order to eliminate these drawbacks, it was proposed in 1983 that polycarbonate could be produced by an interfacial polycondensation reaction between liquid trichloromethyl chloroformate, which is a dimer of phosgene, and a special dihydric phenol instead of toxic phosgene. -182336. However, there is only a description of 9,9-bis(4-hydroxyphenyl)fluorenes, which are special dihydric phenols. It is also Angew to obtain polycarbonate from 2,2-bis(4-hydroxyphenyl)propane using triphosgene instead of toxic phosgene.

Chem, (angebante, hemi-) 99.922 (
(1987), a reaction mechanism in which phosgene is generated has also been proposed. Furthermore, when producing high molecular weight polycarbonate by a transesterification method, many proposals have been made regarding how to soften the reaction conditions to obtain a high molecular weight polycarbonate with good color.

For example, in Japanese Patent Publication No. 47-14742, an initial condensate is prepared from an aromatic dioxy compound and a bisaryl carbonate in the presence of a basic catalyst, and then a quaternary ammonium compound is present to cause a post-condensation reaction of the initial condensate. It has been shown that polycarbonate with excellent thermal stability and hue can be obtained by using this method. Continuing to be a special public official in Showa 47-1474.
In 3, quaternary ammonium and
Similarly, polycarbonate with good color has been obtained using hydroxide. Furthermore, according to USP 4,363,905, a high molecular weight polycarbonate with a good hue is obtained by using a phase transfer catalyst under basic reaction conditions containing a basic catalyst, and as a phase transfer catalyst, quaternary ammonium・It indicates that hydroxide, tetraethylphosphonium hydroxide, etc. are used.

However, even if the transesterification reaction is carried out using the above-mentioned transesterification catalyst, deterioration of the hue cannot be avoided if the polycondensation time is prolonged to obtain a high molecular weight polycarbonate. Further, the catalyst residue is not inactivated, and the heat resistance and hydrolysis resistance are essentially insufficient as shown in the comparative examples.

(Means for Solving the Problems) The present inventors melt-polycondensed bisaryl carbonate and a divalent hydroxy compound as compounds that generate carbonate bonds by a transesterification method in the presence of a transesterification catalyst to produce a phosphite compound. By adding
We have discovered that it is possible to obtain a high molecular weight polycarbonate with two thermally stable hues and excellent hydrolytic stability without using toxic phosgene, essentially containing no chlorine ions, and by inactivating the catalyst residue. .

The present invention is characterized by (1) melt polycondensation of a divalent, droxy compound, and bisaryl carbonate by a transesterification method in the presence of a transesterification catalyst, and adding a phosphite compound and a hindered phenol compound to the obtained polycarbonate. A method for producing polycarbonate. (
2) A method for producing polycarbonate, characterized in that the phosphite compound described in (1) above consists of a compound represented by the following structural formula (I).

(However, R1 represents a hydrocarbon group having 1 to 30 carbon atoms.)
(3) A method for producing polycarbonate, characterized in that the hindered phenol compound described in (1) above consists of a compound represented by the following structural formula (II).

(However, R2 represents a hydrocarbon group having 1 to 30 carbon atoms.)
Typical examples of transesterification catalysts that can be used in the present invention include (a) lithium borohydride, sodium borohydride, potassium borohydride, which are similar to metal-containing catalysts;
Rubidium borohydride, cesium borohydride, beryllium borohydride, magnesium borohydride, calcium borohydride, strontium borohydride, barium borohydride, aluminum borohydride, titanium borohydride, tin borohydride, germanium borohydride, lithium tetraphenoxy, potassium tetraphenoxy, potassium tetraphenoxy, tetraphenoxyrubidium, tetraphenoxycesium, sodium thiosulfate, beryllium oxide, magnesium oxide,
Tin oxide (■), dibutyltin oxide, beryllium hydroxide, magnesium hydroxide, germanium hydroxide, beryllium acetate, magnesium acetate, tin acetate (■), germanium acetate, lithium carbonate, sodium carbonate, potassium carbonate, beryllium carbonate, magnesium carbonate , tin carbonate (■), germanium carbonate, tin nitrate (■), germanium nitrate, antimony trioxide, bismuth trimethyl carboxylate, etc. (b) is an amine compound similar to N,N-dimethyl-4-aminopyridine, 4-diethylaminopyridine, 4-pyrrolidinopyridine, 4-(5-noryl)-pyridine, 4-aminopyridine 2-amino Pyridine 2-hydroxypyridine, 2-methoxypyridine, 4-methoxypyridine, 4-hydroxypyridine2. Dimethylaminoimidazole 2-methoxyimidazole 2-mercaptoimidazole, 2-aminopyridine, aminoquinoline.

Imidazole, 2-methylimidazole, 4. Examples include methylimidazole and diazabicyclooctane (DABCO). (c) or carbonic acid, acetic acid, formic acid, nitric acid, nitrous acid, and oxalic acid of the above-mentioned electron-donating amine compounds.

Examples include fluoroboric acid and hydrofluoride. (
d) Triethylphosphine, tri-n-propylphosphine, triisopropylphosphine, tri-n-butylphosphine, triphenylphosphine, tri-0-dimethoxyphenylphosphine, tri-p-tolylphosphine, which are similar to electron-donating phosphorus compounds.

Examples include tri-tolylphosphine, tributyl phosphite, triphenyl phosphite, tri-p-tolylphosphite, trilotrylphosphite, and the like. (e) Similar to borane complexes, complexes of borane with the following compounds: ammonia, dimethylamine, trimethylamine, triethylamine, t-butylamine, dimethylaniline, pyridine, dimethylaminopyridine, morpholine, piperazine, pyrrole, tetrahydrofuran. , dimethyl sulfide, tri-n-butylphosphine, triphenylphosphine, and complexes with triphenylphosphite.

Moreover, the following compounds are mentioned as typical examples of divalent hydroxy compounds. 2,2-bis-(4-hydroxyphenyl)propane, 2,2-bis-(4-hydroxyphenyl)butane, 2,2-bis-(4-hydroxyphenyl)-4-methylpentane, 2,2- Bis-(4-
hydroxyphenyl)octane, 4,4'-dihydroxy-2,2,2-triphenylethane, 2,2-bis-(3,5-dibromo-4-hydroxyphenyl)propane, 2,2-bis-(4 -hydroxy-3-methylphenyl)propane, 2,2-bis-(4-hydroxy-
3-isopropylphenyl)propane, 2.2-bis-(4-hydroxy-3-sec, butylphenyl)propane.

2.2-bis-(3,5-dimethyl-4-hydroxyphenyl)propane, 2,2-bis, (4-hydroxy-
3-tert-butylphenyl)propane, 1,1
'-bis-(4-hydroxyphenyl)-p-diisopropylbenzene, 1.1'-bis-(4-hydroxyphenyl)-m-diisopropylbenzene, 1,1-bis-(4-hydroxyphenyl)cyclohexane, etc. Can be mentioned. Furthermore, two or three types selected from the above
It is also possible to produce copolycarbonates in which more than one type of divalent hydroxy compound is combined.

Furthermore, the structural formula (I) used in the present invention is tris(4
-nonylphenyl phosphite), the structural formula (I) is octadecyl-3-(3',5'-di-t-butyl-4-
Hydroxyphenyl)propionate is preferred. Typical examples of bisaryl carbonates include diphenyl, carbonate, bis(2,4-dichlorophenyl) carbonate, bis(2,4,6-)lychlorphenyl) carbonate, and bis(2-cyanophenyl) carbonate. , bis(0-nitrophenyl) carbonate, ditolyl carbonate, and other unsubstituted and nuclear-substituted bisaryl carbonates.

The method of the present invention is carried out by melt polycondensation reaction of a divalent hydroxy compound such as bisphenol A with a bisaryl carbonate by a transesterification method using a catalyst selected from transesterification catalysts.

The temperature at which this reaction proceeds ranges from over 100°C to approximately 300°C.
The range is up to C. Preferably from 130°C to 280°C
°C range. If the temperature is less than 130°C, the reaction rate will be slow, and if it exceeds 280°C, side reactions will likely occur.

The transesterification catalyst used as a catalyst is 10-1 mol to 1 mol based on the divalent hydroxy compound present in the reaction system.
0-5 moles are required, preferably 10-2 to 10-4 moles. If it is less than 10-5 mol, the catalytic effect will be low and the polymerization rate of polycarbonate will be slow.
If the amount is 0-1 mol or more, the proportion remaining as a catalyst in the polycarbonate produced will be high, leading to deterioration of the physical properties of the polycarbonate. Tris(4-nonylphenylphosphite) and octadecyl-3-(3',5
'-di-t-butyl-4-hydroxyphenyl) propionate is added to the polycarbonate, and the amount of phosphite compound added is 0.0 based on the total amount of polymer.
It is added from 1% to 0.5% by weight, but preferably,
0.03% to 0.3% by weight. Addition amount is 0.
If it is less than 0.03% by weight, it will not be effective as a stabilizer and will have an adverse effect on the heat resistance and hydrolysis resistance of the polycarbonate. Moreover, if it exceeds 0.3% by weight, it will adversely affect the mechanical properties of polycarbonate.

Some of the polymers obtained in this way are used as engineering plastic materials, especially for outdoor applications such as outdoor lighting equipment, window glass, fences, microwave ovens, etc.
Suitable as a material for applications that are exposed to high temperature and humidity, such as tableware, tanks, and transport pipes.

It can also be applied to heat-sensitive elements such as electric blankets and carpets, various hoses, tubes, hot melt adhesives, and the like.

The present invention will be described below with reference to Examples, but the present invention includes:
The invention is not limited to these examples.

(Example) Example 1 2.2-bis(4-hydroxyphenyl)propane 22
8 parts by weight, potassium borohydride (10'mo1% based on the charged dihydroxy compound), and 214 parts by weight of diphenyl carbonate were added, stirred at 180°C for 1 hour under nitrogen, and then gradually heated to 250°C. The pressure inside the C1 system is also 2m.
It was lowered to mHg. Continue to raise the temperature to 280°C10.5mm
Polycarbonate was obtained by reacting with Hg for 2 hours. This polycarbonate is almost colorless and transparent, and contains methylene and
Intrinsic viscosity measured in chloride solution at 20°C [r1]
is 0.438 [rll=1.11X10-'(Mv)
0.82 [Encyclopedia of Polymer Science and Technology, Vol. 10, p. 732, 1969, John Quisoe and Sons, Inc.; Encyclopedia of Polymer
5science and Technology V
ol 10 P732; John Wiley &
The average molecular weight MV calculated using the formula 5onsInc (1969) was 24,300. 254 g of the polycarbonate thus obtained was
nonylphenyl phosphite) and octadecyl-3-(
0.254 g each of 3', 5'-di, t-butyl-4-hydroxyphenyl) propionate (each 0.1% by weight based on the polymer) was mixed in a tumbler blender (Matsui Seisakusho Niskabee 50; 5KB-50). , twin screw extruder (HAAKEBuchler Product H System 90/HAAKEBuchler Product H
It was extruded using a BI System 90) and made into pellets. As an evaluation of heat resistance, temperature increase rate 1 in nitrogen stream
Thermal decomposition behavior was measured using a differential thermogravimetric analyzer (manufactured by Rigaku Denki Co., Ltd.) under conditions of 0°C/min. The decomposition start temperature (Td) is 430°C. The temperature at which the weight loss reaches 5% (T
5) is the temperature at which the weight loss reaches 10% at 467°C (Tl
o) was 481°C.

In addition, in order to evaluate the hydrolysis resistance, 50%
Create a sheet 9 mm x 50 mm x 0.6 mm thick.
The sample was suspended in a constant temperature and humidity chamber at 0°C, 100% RH, and the decrease in molecular weight due to hydrolysis was measured. 90°C1100%
After 30 days under RH (relative humidity) conditions, the molecular weight retention rate with respect to the initial molecular weight was 88.0%, and the appearance of the sheet was colorless and transparent, with no abnormalities observed.

Example 2 2.2-bis(4-hydroxyphenyl)propane 22
．． 8 g (0.1 mol) and 0.1 2-methylimidazole
Add 64g (2X10-2 mol) and 21.4g (0.1 mol) of diphenyl carbonate and stir at 180°C for 1 hour under nitrogen, then gradually raise the temperature to 250°C and lower the pressure inside the system. When the temperature reached 2 mmHg, tris(4-nonylphenylphosphite) and octadecyl-3-(3',5
0.025 g each of '-di-t-butyl-4-hydroxyphenyl)propionate (0.025 g each based on the total polymerization).
1% by weight) was added.

Estimated relative solution viscosity obtained from the stirring torque at the time of this addition (polymer concentration: 0.5 g / 100 m1
．． (20°C, methylene chloride solvent) was 1.17, and the relative solution viscosity obtained by sampling a small amount of a partially polymerized product was 1.18. Continue to raise the temperature to 280
A polycarbonate was obtained by reacting at 5 mmHg for 2 hours. This polycarbonate is almost colorless and transparent, and has an intrinsic viscosity measured at 20°C in a methylene chloride solution. ] is 0.519 and [r1] = 1.11
X 10-' (Mv) 0.82 [Encyclopedia of Polymer Science and Technology Volume 10 7
32 pages 1969 John Quisoe and Sons Inc.;
Encyclopedia of Polymer 5
Science and Technology Vol.
10 P732; John Wiley & 5o
The average molecular weight VV calculated using the formula nsInc (1969) was 29,900.

Example 3 Under exactly the same conditions as in Example 1, dimethylamine borane complex (2 mo% of 1 based on the charged dihydroxy compound) was added instead of sodium borohydride, and a reaction was carried out to obtain polycarbonate. . Further, in the same manner as in Example 1, the pellets were formed into pellets and their heat resistance and hydrolysis resistance were evaluated.

The results are shown in Table 1.

Example 4 2.2-His(4-hydroxyphenyl)propane 1
14 parts by weight (50 mol%), 170 parts by weight (50 mol%) of 2,2-bis(4-hydroxy-3-t-butylphenyl)propane, 214 parts by weight of diphenylnia'J-,Nate, 4- Dimethylaminopyridine (10-2m01% based on the charged dihydroxy compound) was added and the reaction was carried out under exactly the same conditions as in Example 1 to obtain a polycarbonate copolymer. The pellets were formed into pellets in the same manner as in Example 1, and the heat resistance and hydrolysis resistance were evaluated. The results are shown in Table 1.

Example 5 2.2-bis(4-hydroxyphenyl)propane 22
．． 8 g (0.1 mol), bis(2,4,6-)lichlorophenyl)carbonate 42.1 g (0.1 mol), dimethylaminopyridine 0.0122 g (10-4 mol)
After stirring under nitrogen for 180°C, the temperature was gradually increased while reducing the pressure, and when the relative solution viscosity reached 1.19, tris(4-nonylphenylphosphite) and octadecyl were stirred in the same manner as in Example 2. -3-(3',5'-di-t-butyl-4-hydroxyphenyl)propionate, each with 0
．． 025g was added to carry out the reaction.

Table 1 shows the hue, viscosity average molecular weight, thermal decomposition behavior and hydrolysis behavior of the obtained polymer.

(Comparative example) Comparative example 1 Tris (4-nonylphenyl phosphite) and octadecyl-3-(3
',5'-di,t-butyl-4-hydroxyphenyl)
The pellets were formed into pellets without adding propionate, and the heat resistance and hydrolysis resistance were evaluated. The results are shown in Table 1.

Comparative Example 2 In Example 2, for comparison, lithium hydroxide, which is an alkali metal hydroxide, was used in an amount of 10-3 mol% based on the total 2,2-bis(4-hydroxyphenyl)propane as a known catalyst. The reaction was carried out without adding 4-nonylphenyl phosphite) and octadecyl-3-(3',5'-di-t,butyl-4-hydroxyphenyl)propionate.

The obtained polymer had a high average molecular weight of 26,500, but was pale yellow in color, and thermal decomposition started at 375°C and a weight loss of 10% was observed at 430°C. Also, 90°
C1 After 30 days in a hydrolysis test at 100% RH, the average molecular weight retention remained at 65.3%, and the test sheet became cloudy and small white spots (including some voids).
A large number of defects occurred over the entire surface, and embrittlement was remarkable. These results are shown in Table 1.

(Effects of the invention) As shown in the results in Table 1, by adding a specific phosphite compound and a specific hindered phenol compound to an aromatic polycarbonate polymer, the heat resistance and hydrolysis resistance of the resin composition obtained It has improved properties and can be used in various fields as an engineering plastic material.

Claims (2)

[Claims] (1) A phosphite compound and a hindered phenol compound are added to a polycarbonate obtained by melt polycondensation of a divalent hydroxy compound and a bisaryl carbonate by transesterification reaction in the presence of a transesterification catalyst. Method of manufacturing polycarbonate. (2) A method for producing polycarbonate, characterized in that the phosphite compound according to claim 1 comprises a compound represented by the following structural formula (I). ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I) (However, R_1 represents a hydrocarbon group having 1 to 30 carbon atoms.) (3) The hindered phenol compound described in claim 1 is A hindered phenol compound having structural formula (II). ▲There are mathematical formulas, chemical formulas, tables, etc.▼(II) (However, R_2 represents a hydrocarbon group having 1 to 30 carbon atoms.)